<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>发光的毛毛球</title>
    <style>
        body {
            background-color: #000;
        }
        .ball {
            width: 200px;
            height: 200px;
            background: radial-gradient( yellow 5%, transparent 70%);
            border: 1px solid red;
        }
    </style>
</head>
<body>
    <div class="ball"></div>
</body>
</html>
